1. Field of the Invention
The present invention relates to the grounding structure of a semiconductor device.
2. Description of the Related Art
An SOI (Silicon On Insulator) type semiconductor device has an insulating film like a silicon oxide formed on a semiconductor substrate, and an integrated circuit formed thereon. According to this structure, the integrated circuit including thin film transistors is surely insulated from the semiconductor substrate, thereby facilitating complete inter-device isolation and reducing various parasitic capacitances, resulting in sufficient suppression of degrading of the device characteristics. This makes it possible to suppress latch up which is peculiar to CMOS-transistor circuits. Accordingly, speeding-up of an integrated circuit with low voltage operation is facilitated, and the reliability thereof is improved.
Unexamined Japanese Patent Application KOKAI Publication No. 2003-218356 discloses such a structure that an SOI type semiconductor device is bonded on a circuit substrate. The package of the semiconductor device disclosed in this publication has the SOI type semiconductor device on a lead frame by a face-up scheme, i.e., with an integrated circuit being faced up, and each connection pad of the integrated circuit is connected to the lead frame by wire bonding. According to this semiconductor package, a conductive adhesion layer fixes the semiconductor device to the lead frame, and the lead frame is grounded, thereby stabilizing the electric potential of the semiconductor device.